Second-Order State Variable Filter Consumes Less Than 3 µA

Filters are used in many applications to remove unwanted frequency components from incoming signals, enhance incoming signals, or both. In portable and non-portable medical applications, for example, the heart-rate functionality must detect a range of frequencies. Similarly, handheld communication products like walkie-talkies must be able to monitor multiple tones. In these and other applications, the combination of a low pass, …